projects / binutils.git / blame
| Commit | Line | Data |
|---|---|---|
| 11bb3205 CF |
1 | /* List implentation of a partition of consecutive integers. |
| 2 | Copyright (C) 2000 Free Software Foundation, Inc. | |
| 3 | Contributed by CodeSourcery, LLC. | |
| 4 | ||
| 5 | This file is part of GNU CC. | |
| 6 | ||
| 7 | GNU CC is free software; you can redistribute it and/or modify | |
| 8 | it under the terms of the GNU General Public License as published by | |
| 9 | the Free Software Foundation; either version 2, or (at your option) | |
| 10 | any later version. | |
| 11 | ||
| 12 | GNU CC is distributed in the hope that it will be useful, | |
| 13 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
| 15 | GNU General Public License for more details. | |
| 16 | ||
| 17 | You should have received a copy of the GNU General Public License | |
| 18 | along with GNU CC; see the file COPYING. If not, write to | |
| 19 | the Free Software Foundation, 59 Temple Place - Suite 330, | |
| 20 | Boston, MA 02111-1307, USA. */ | |
| 21 | ||
| 22 | /* This package implements a partition of consecutive integers. The | |
| 23 | elements are partitioned into classes. Each class is represented | |
| 24 | by one of its elements, the canonical element, which is chosen | |
| 25 | arbitrarily from elements in the class. The principal operations | |
| 26 | on a partition are FIND, which takes an element, determines its | |
| 27 | class, and returns the canonical element for that class, and UNION, | |
| 28 | which unites the two classes that contain two given elements into a | |
| 29 | single class. | |
| 30 | ||
| 31 | The list implementation used here provides constant-time finds. By | |
| 32 | storing the size of each class with the class's canonical element, | |
| 33 | it is able to perform unions over all the classes in the partition | |
| 34 | in O (N log N) time. */ | |
| 35 | ||
| 36 | #ifndef _PARTITION_H | |
| 37 | #define _PARTITION_H | |
| 38 | ||
| 39 | #ifdef __cplusplus | |
| 40 | extern "C" { | |
| 41 | #endif /* __cplusplus */ | |
| 42 | ||
| 43 | #include <ansidecl.h> | |
| 44 | #include <stdio.h> | |
| 45 | ||
| 46 | struct partition_elem | |
| 47 | { | |
| 48 | /* The canonical element that represents the class containing this | |
| 49 | element. */ | |
| 50 | int class_element; | |
| 51 | /* The next element in this class. Elements in each class form a | |
| 52 | circular list. */ | |
| 53 | struct partition_elem* next; | |
| 54 | /* The number of elements in this class. Valid only if this is the | |
| 55 | canonical element for its class. */ | |
| 56 | unsigned class_count; | |
| 57 | }; | |
| 58 | ||
| 59 | typedef struct partition_def | |
| 60 | { | |
| 61 | /* The number of elements in this partition. */ | |
| 62 | int num_elements; | |
| 63 | /* The elements in the partition. */ | |
| 64 | struct partition_elem elements[1]; | |
| 65 | } *partition; | |
| 66 | ||
| 67 | extern partition partition_new PARAMS((int)); | |
| 68 | extern void partition_delete PARAMS((partition)); | |
| 69 | extern int partition_union PARAMS((partition, | |
| 70 | int, | |
| 71 | int)); | |
| 72 | extern void partition_print PARAMS((partition, | |
| 73 | FILE*)); | |
| 74 | ||
| 75 | /* Returns the canonical element corresponding to the class containing | |
| 76 | ELEMENT__ in PARTITION__. */ | |
| 77 | ||
| 78 | #define partition_find(partition__, element__) \ | |
| 79 | ((partition__)->elements[(element__)].class_element) | |
| 80 | ||
| 81 | #endif /* _PARTITION_H */ |